Air compressor

Abstract

An air compressor includes a cylinder being fitted with a piston body and an air storage container formed integrally with the cylinder The air storage container defines therein an air chamber having a diameter greater than or equal to the inner space of the cylinder A pressure relieving mechanism is directly mounted to the air storage container rather than at one outlet provided at the air storage container, wherein one portion of the pressure relieving mechanism is located in the air chamber of the air storage container while the other portion of the pressure relieving mechanism extends out of the air storage container to be in contact with a push button provided on an external enclosure, whereby a user may depress the push button to reduce the air pressure within the air storage container.

I claim: 
     
       1. An air compressor that includes
 an external enclosure and 
 an electrically-operated compressor unit inside the external enclosure,
 the compressor unit including
 a cylinder and 
 an air storage container defining therein an air chamber that communicates with an inner space of the cylinder, 
 
 the cylinder being fitted with a piston body driven by a motor for conducting reciprocating motion for producing compressed air in the inner space of the cylinder, a valve mechanism controlling the compressed air to enter the air chamber of the air storage container; 
 wherein the improvement comprises:
 a pressure relieving mechanism is mounted to the air storage container, 
 wherein one portion of the pressure relieving mechanism is located in the air chamber of the air storage container while the other portion of the pressure relieving mechanism extends out of the air storage container to be actuated by a user for reducing the air pressure within the air storage container, 
 wherein the pressure relieving mechanism includes 
 a stem, 
 a seal ring, and 
 a compression spring, 
 the stem having 
 
 a resilient head at one end, 
 a bottom plate at the other end, 
 a neck next to the bottom plate, and 
 a protrusion next to the neck, 
 wherein the seal ring is fitted around the neck of the stem, 
 the stem is inserted through a through hole of the air storage container and fitted with the compression spring such that the resilient head is located outside the air storage container while the bottom plate is located inside the air storage container, 
 the seal ring is engaged between the bottom plate and the air storage container, and 
 the compression spring is disposed between the resilient head and the air storage container such that the seal ring normally seals the through hole, whereby depressing the resilient head will move the stem inwardly of the air storage container, so that the compressed air within the air storage container can be released into the ambient environment by way of the through hole of the air storage container, thereby reducing the air pressure. 
 
 
     
     
       2. An air compressor that includes
 an external enclosure and 
 an electrically-operated compressor unit inside the external enclosure,
 the compressor unit including
 a cylinder and 
 an air storage container defining therein an air chamber that communicates with 
 
 an inner space of the cylinder, 
 the cylinder being fitted with a piston body driven by a motor for conducting reciprocating motion for producing compressed air in the inner space of the cylinder, a valve mechanism controlling the compressed air to enter the air chamber of the air storage container; 
 wherein the improvement comprises: 
 
 a pressure relieving mechanism is mounted to the air storage container, 
 wherein one portion of the pressure relieving mechanism is located in the air chamber of the air storage container while the other portion of the pressure relieving mechanism extends out of the air storage container to be actuated by a user for reducing the air pressure within the air storage container, 
 wherein the air storage container is comprised of a main container shell and 
 a cover, 
 the main container shell is formed integrally with the cylinder at its bottom, 
 the cover being capable of sealing an open top of the main container shell to define therein the air chamber, 
 the air chamber has a diameter greater than or equal to the inner space of the cylinder, 
 the main container shell and the cylinder sharing a partition wall that defines a through hole communicating the air chamber with the inner space of the cylinder, 
 a plurality of posts being formed on a top surface of the partition wall and arranged around the through hole thereof to define a central space therebetween, 
 the valve mechanism including
 a plug and 
 a compression spring disposed between the cover and the plug, 
 the plug being urged by the compression spring and located in the central space surrounded by the posts so that the plug can be prevented from lateral movement under a force, 
 the open top of the main container shell being formed with a first coupling means that includes two substantially opposite lateral plates extending outwardly from the surrounding wall of the main container shell, 
 
 one side of each lateral plate being formed into a first holding portion defining a first recess. 
 
     
     
       3. The air compressor of  claim 2 , wherein a second through hole is defined on the main container shell to communicate the air chamber with the ambient environment,
 the portion of the pressure relieving mechanism which extends out of the air storage container passes through the second through hole and is located outside the main container shell, and 
 actuation of the portion of the pressure relieving mechanism which extends out of the air storage container allows the compressed air within the air chamber to be released into the ambient environment. 
 
     
     
       4. The air compressor of  claim 3 , wherein the pressure relieving mechanism includes
 a stem, 
 a seal ring, and 
 a stem compression spring, the stem having 
 a resilient head at one end, 
 a bottom plate at the other end, 
 a neck next to the bottom plate, and 
 a protrusion next to the neck, 
 wherein the seal ring is fitted around the neck of the stem, 
 the stem is inserted through the second through hole of the main container shell and fitted with the stem compression spring such that the resilient head is located outside the main container shell and in contact with a push button provided on the external enclosure while the bottom plate is located inside the main container shell, 
 the seal ring is engaged between the bottom plate and the main container shell, and the stem compression spring is disposed between the resilient head and the main container shell so that the seal ring normally seals the second through hole of the main container shell, whereby depressing the push button will move the stem inwardly of the main container shell, so that the compressed air within the air chamber of the air storage container can be released into the ambient environment by way of the second through hole of the main container shell, thereby reducing the air pressure. 
 
     
     
       5. The air compressor of  claim 2 , wherein the cover is a flat body having two substantially opposite lateral plates, one side of each lateral plate of the cover being formed into a second holding portion defining a second recess, the outer surface of the cover being provided with radial ribs to facilitate a user to operate the cover, the cover being formed with a tubular connection portion extending downwardly from its inner surface, the tubular connection portion defining an annular groove around its circumference to be fitted with a seal ring, the inner surface of the cover being further formed with a central column and an annular protrusion around the central column, thus defining an annular groove between the central column and the annular protrusion, one end of the compression spring of the valve mechanism is fitted around the central column and received in the annular groove; whereby the tubular connection portion of the cover is capable of being inserted into the main container shell, and the cover is capable of being rotated about the main container shell to allow its lateral plates to slide in the first recesses of the main container shell, and allow the lateral plates of the main container shell to slide in the second recesses, so that the cover is detachably mounted to the main container shell and thus seals the open top of the main container shell. 
     
     
       6. The air compressor of  claim 2 , wherein the cover is a cylindrical body having a tubular connection portion formed at its open bottom,
 the tubular connection portion defining an annular groove around its circumference to be fitted with a seal ring, 
 the cover defining a second through hole at the surrounding wall thereof, 
 the cover being provided at its top inner surface with a central column and an annular protrusion around the central column, thus defining an annular groove herebetween, 
 the cover being further provided with a plurality of spaced bars extending from a bottom of the annular groove and arranged around the central column, each of the bars having a bottom edge, the pressure relieving mechanism including a stem, a seal ring, and a stem compression spring, the stem having a resilient head at one end, a bottom plate at the other end, a neck next to the bottom plate, and a protrusion next to the neck, wherein the seal ring is fitted around the neck of the stem, the stem being inserted through the second through hole of the cover and fitted with the stem compression spring such that the resilient head is located outside the cover while the bottom plate is located inside the cover, the stem compression spring being disposed between the resilient head and the cover, and the seal ring being engaged between the bottom plate and the cover. 
 
     
     
       7. The air compressor of  claim 6 , wherein the plug has three coaxial round
 portions including
 a bottom round portion, 
 a middle round portion, and 
 a top round portion, 
 the bottom round portion having a diameter greater than the middle round portion, 
 the middle round portion having a diameter greater than the top round portion, 
 the plug being located in the central space surrounded by the posts so that the plug is confined by the posts to prevent it from lateral movement under a force, 
 the diameter of the bottom round portion being smaller than the diameter of the central space surrounded by the posts but greater than the diameter of the through hole of the partition wall, 
 one end of the compression spring being fitted around the top round portion of the plug while urged against the middle round portion, the other end of the compression spring is fitted around the central column and engaged the bottom edges of the bars.